Apparatus for treatment of waste thermoplastic synthetic fibers



May 19 1964 E. G. wHALoN ETAL 3 133 33 APPARATUS FOR TREATMENT OF WASTE THERMOPLASTIC 5 SYNTHETIC FIBERS Original Filed July 19, 1960 n mnnnnmqur 2 s; E s 1 I o 7S lNvENToRs Q, l i, l ERNEST G.wHALoN THOMAS R510 g j ANTHONY osowsm ATTORNEY United States Patent O 1 Claim. (Cl. 28--71.3)

This is a division of our prior application Serial No. 43,926, iiled by us on July 19, 1960, and relates to an improved apparatus for the advantageous treatment of waste thermoplastic synthetic fibers which are ordinarily removed from a spool, upon which they are Wound directly from the formation thereof, by cutting the material in an axial direction to remove it from the spool so as to reclaim the spool for immediate re-use, the waste material then being processed by garnetting, carding, dyeing, etc., whereafter it may be spun into yarn. But in this case the yarn has to be stretched and the bers are f random length due to the cutting, garnetting and carding operations. It is the principal object of the present invention tov provide an apparatus for obtaining high quality yarn from such waste thermoplastic synthetic filaments in which the yarn is of uniform length staple fibers, resulting in a greatly improved yarn made from the waste; and the provision of an apparatus for providing the uniform length staple fibers from waste thermoplastic synthetic filaments much faster and much less expensively than the inferior yarn of random ber length was capable of being produced in the prior art, part of this result being due to a novel method of massive stretching of the filaments prior to crimping and spinning, as well as completely obviating the prior art steps of garnetting, carding, etc.

The invention further relates to arrangements and combinations of parts which will be hereinafter described and more particularly set forth in the appended claim.

Reference is to be had to the accompanying drawing, in which:

FIG. l is a diagram in plan, and

FIG, 2 is a side elevation thereof.

The present invention may be carried out by means of apparatus as disclosed in the drawing diagrammatically wherein the reference numeral indicates in general a series of spools 12, in this case twelve in number, upon each of which is wound stranded filaments of waste synthetic thermoplastic materials such as nylon. These each provide an end 14 and these ends are led over guides or the like 16 and down to a bath at 18, this bath not being pertinent to the novelty of the present invention.

The twelve ends are all separate as shown in FIG. 1 and these ends are kept separate through the bath at 18 by a conventional guide mechanism or the like 20 which may be a series of individual guides holding the separate strands independent of each other. Then the ends wrap around a lower roll 22 of a pair of rolls, the upper one of which is indicated at 24.

The rolls in this case are shown as three pairs and they may be essentially the same. These rolls are extremely heavy and may weigh about a ton-and-a-half, for example.

At the rst pair of rolls indicated at 22 and 24, an additional e.g. five thousand pounds of pressure is applied 011 the top roll 24, and it will be seen that an extremely powerful drag is imparted to the twelve ends which are indicated to the right of the roll pair 22, Z4 as at 26. In this area, a great deal of stretch is removed from the synthetics.

The twelve ends proceed from the area 26 to the lower roll 28 of another pair of rolls, the upper of which is shown at 30. In this case the rolls are the same as before 3,133,335 Patented May 19, 1964 ICC described, being smooth-surfaced pressure rolls, but in this case it has been found that there is no need to add any extra pressure to the upper roll 3l). The twelve ends still separate, then proceed into the area 32 where the remainder of the stretch is removed, the ends wrapping around a pair of rolls 34 and 36 which are again the same as previously described. In this case live thousand pounds pressure or the like is applied to the upper roll 36, and it is pointed out that all of the rolls are driven rolls, those at 34 and 36 rotating faster than the intermediate rolls 28 and 30, and rolls 28 and 30 rotating faster than the rolls at 22 and 24 by any usual power means.

The twelve ends converge in the area indicated at 38 to a collector or condenser 40 and then proceed in a single tow 42 to be wound on a roll at 44.

The strands of filaments which appear on the rolls at 12 are each in the nature of three hundred and fifty thousand denier. The stretch elongation is approximately in the ratio of one to 3.6 and in the area at 38 each of the twelve ends is in the nature of one hundred thousand denier. Since there are twelve of these ends, they are condensed at 40 into a single strand of many laments which is approximately 1,200,000 denier, and this is then wrapped on the spool as at 44.

The material appearing on the spools 12 is waste nylon, Dacron or similar thermoplastic synthetic stranded filaments. It has to be emphasized that this is waste material and that ordinarily the waste is merely cut from the rolls at the mill where the strands are produced and is then sold to garnetters or other processors who cut it, garnett, card, crimp, and whatever other process is desired to be applied thereto in order to prepare the same for spinning into yarn. Obviously when the waste is processed in this manner, the iibers are going to be random length fibers. The present method which has been described above, however, utilizes the waste material not in the form of cut fibers, but in the form of substantially continuous or endless fibers, at least insofar as each roll 12 is concerned, so that the stretch is completely eliminated from these continuous iibers when the same is wound on roll 44, but the iibers have not been cut.

This process allows the processor to take the tow on roll 44, steam it, crimp it, heat it to make the crimp permanent, and then cut it into tops, all of which have exactly equal liber length whatever the length of the cut pieces may be, and when this uniform liber length material is then processed further, so that it can be spun into yarn, it provides a very high-grade, uniform length staple yarn, as distinct from the random length fiber yarn heretofore produced from the waste.

Having thus described our invention and the advantages thereof, we do not wish to be limited to the details herein disclosed, otherwise than as set forth in the claim, but what we do claim is:

Apparatus of the class described comprising:

(a) a source of supply of a plurality of large total denier strands of substantially unstretched thermoplastic synthetic continuous filaments wound separately on cores;

(b) guide means above said cores for guiding said strands removed from said cores separately in substantially parallel spaced relation;

(c) a first pair of heavy superposed nip-forming pressure rolls for forwarding said strands thereto from said source of supply in one direction and for exiting said strands from the nip thereof in the opposite direction to provide wrap around one of the rolls;

(d) means for driving said iirst pair of rolls at a first peripheral speed;

(e) means for applying positive pressure to the nip of said first pair of rolls;

(f) a second pair of heavy superposed nip-forming rolls for forwarding said strands thereto from said rst pair of rolls in one direction and for exiting said strands from the nip of the second pair of rolls in the opposite direction to provide Wrap around one of the rolls of the second pair of rolls;

(g) means for driving said second pair of rolls at a peripheral speed greater than the rst pair of rolls;

(lz) a third pair of heavy superposed nip-forming rolls for forwarding said strands thereto from said second pair of rolls in one direction and for exiting said strands from the nip of the third pair of rolls in the opposite direction to provide wrap around one of the rolls of the third pair of rolls;

(i) means for applying positive pressure to the nip of said third pair of rolls;

(j) means for driving said third pair of rolls at a peripheral speed greater than the second pair of rolls;

(k) guide means in the strand path beyond the exit of the nip ofthe third pair of rolls for gathering together the strands for the rst time into one massive strand; and

(l) means for winding the stretched single massive strand on a single core.

References Cited in the le of this patent UNITED STATES PATENTS 

